Summary: AWARDS ADMINISTERED
July 2005 ­ June 2006
NOTE: Dates in green are the projected end dates and dollar value in green is the projected total award
value.
____________
Guenter Ahlers
National Aeronautics and Space Administration, NAG3-2872
Boundary Effects on Transport Properties and Dynamic Finite-Size Scaling Near
the Superfluid-Transition Line of 4
He
03/26/03-09/30/07
$614,000
We extended the analysis of the thermal conductivity measurements of helium confined in cylindrical
channels of glass capillary arrays to the case of rectangular channels. Measurements were made on
plates with channels of 1x10 micro-m cross section, and simultaneously on bulk helium. To our great
surprise the results show that the finite-size scaling-function for this geometry does not differ
measurably from the scaling function for cylindrical confinement. This differs qualitatively from what
had been found for thermodynamic properties in one-dimensional and two-dimensional confinement.
We have now started the measurements of the heat capacity in the same micro-channel plates.
Knowledge of this is necessary for the complete theoretical interpretation of the conductivity data.